Change of circumstances

Hi i am really not happy as I have been calling student finance for a some time and being told things differently.

What it is is last year I stopped university and went back this year so my payments were blocked and student finance requested coc from my university.I sent the change of circumstances and i was told payments will be unblocked after 3 working days and then money will come in after another 3 to 5 working days.However nothing has changed up to now as this is the 3rd working day and when I called i was advised it takes 20 working days to process change of circumstances and thats now different from the3 days i was told before.Please advice me how long it really takes.